The invention relates generally to printing mechanisms, and more particularly to an improved spittoon for receiving and storing waste ink ejected during printhead servicing.
Inkjet printing mechanisms generally include one or more pens that eject small drops of liquid colorant, generally referred to herein as xe2x80x9cink,xe2x80x9d onto a print media. Each pen has a printhead that incorporates very small nozzles through which the ink drops are fired. When the ink nozzles become obstructed or blocked, the print quality of the printer is degraded. The printhead must therefore occasionally be serviced. Printhead nozzles are typically cleared by firing a number of drops of ink through each of the nozzles in a process known as xe2x80x9cspitting.xe2x80x9d This waste ink is generally collected in a waste ink reservoir that is typically part of a printhead service station. The waste ink reservoir is often referred to as a xe2x80x9cspittoon.xe2x80x9d
Earlier spittoon designs feature substantially straight spittoon walls and open spittoon tops. Even if a spittoon is partially enclosed with a bonnet, the joint between the spittoon base and the bonnet is not liquid-tight, and leaks if the liquid level reaches the joint. If a printer containing such a spittoon is tipped or moved while the spittoon contains a substantial volume of liquid waste ink, the waste ink can leak into the interior of the printer, or even onto the operator or the operator""s belongings. The potential for spilling the waste ink also exists whenever the spittoon is emptied or replaced, even when the printer itself remains stationary and level.
A spittoon for servicing a printhead is provided, where the spittoon includes a reservoir for waste ink, and incorporates a precipitating agent within the reservoir, wherein the precipitating agent is selected to react with a component of the waste ink to form a precipitate. At least one wall of the spittoon has an inwardly extending lip, so that the spittoon may be tilted without spilling the waste ink.